Carbon dioxide capture and sequestration have gained significant attention over the last decade due in part to concerns over the role carbon dioxide may play as a greenhouse gas in relation to climate change or global warming. One approach that has been suggested for capturing carbon dioxide involves electrolytic salt splitting in an aqueous system to prepare a hydroxide, which may then be reacted with gaseous carbon dioxide to capture the carbon dioxide in the form of a carbonate. Processes have been proposed using a variety of salts in electrolyte solutions subjected to electrolysis, including the use of sodium chloride or sodium sulfate. Some proposed processing, equipment and systems involving the use of some sulfate salts, including sodium sulfate, are described in U.S. Patent Publication 2008/0245660 entitled “RENEWABLE ENERGY SYSTEM FOR HYDROGEN PRODUCTION AND CARBON DIOXIDE CAPTURE”; U.S. Patent Publication 2008/0245672 entitled “ELECTROCHEMICAL METHODS TO GENERATE HYDROGEN AND SEQUESTER CARBON DIOXIDE”; and U.S. Patent Publication 2008/0248350 “ELECTROCHEMICAL APPARATUS TO GENERATE HYDROGEN AND SEQUESTER CARBON DIOXIDE”; the contents of each and every one of which is incorporated by reference herein in entirety.
Technologies directed to sequestering carbon dioxide must be scalable to a very large scale, on the order of being able to capture millions of tons of carbon dioxide. At such a large scale, implementation of such technologies will need to be both economic and environmentally sound.